navigation not working 100% on mobile devices (2 posts)

i have a website: http://www.davidbalber.com that appears and acts 100% perfectly on the computer. on mobile devices such as my iphone or ipad, everything works find EXCEPT...when the ipad is in portrait mode, or the iphone is being used and then you click the navigation icon, under GALLERY, then under COMMERCIAL, it shows the various projects, but alas it won't let you click on those links for some reason. it will let you click any other link so i have no idea why it is singling out the COMMERCIAL links. any help would be greatly appreciated.

also i haven't tested it on a PC based phone like a droid, so if anyone could do that and tell me how it behaves that would help too. thanks!